17 resultados para IMMUNOLOGICAL PHAGOCYTOSIS
em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain
Resumo:
A pure sensory neuropathy caused by lymphocytic infiltration of the dorsal root ganglia has been reported in a few patients with Sjögren's syndrome. The clinical, immunological, and electromyographic findings of five patients with this type of neuropathy and primary Sjögren's syndrome were reviewed. Typical clinical indications were the presence of a chronic asymmetrical sensory deficit, initial disease in the hands with a predominant loss of the vibratory and joint position senses, and an association with Adie's pupil syndrome or trigeminal sensory neuropathy. The simultaneous impairment of the central and peripheral evoked cortical potentials suggested that there was a lesion of the neuronal cell body. The neuropathy preceded the diagnosis of Sjögren's syndrome in four patients. Four patients were positive for Ro antibodies, but systemic vasculitis or malignancy was not found after a mean follow up of six years. These findings indicate that in patients with a sensory neuropathy the diagnosis of Sjögren's syndrome has to be considered, even if the patient denies the presence of sicca symptoms, and that appropriate tests must be carried out.
Resumo:
Chronic obstructive pulmonary disease (copd) is a major cause of illness and death throughout the world. It affects about 10% of the general population, but its prevalence among heavy smokers can reach 50%.COPD is the fourth leading cause of death in most industrialized countries, and it is projected to be the third leading cause of death worldwide by 2020. Tobacco smoking is the primary risk factor for the development of COPD, but other factors, such as burning biomass fuels for cooking and heating, are important causes of COPD in many developing countries....
Resumo:
Systemic lupus erythematosus (SLE) predominantly affects young women in their 20s. In 40 out of 250 (16%) patients with SLE seen in our hospital disease onset occurred after the age of 50. The interval between the time of onset and diagnosis was five years in this older group compared with three years in the younger group. Arthritis, as a first symptom, was less common in the older onset group. During the follow up a lower incidence of arthritis, malar rash, photosensitivity, and nephropathy was found in the older onset group. In contrast, this group showed an increased incidence of myositis. High titres of anti-dsDNA tended to occur less often and the incidence of anti-Ro antibodies was lower in the older onset group. These features seem to distinguish patients with older onset SLE as a particular subset.
Resumo:
Although systemic lupus erythematosus (SLE) has traditionally been considered a disease of women, men may also be affected. Thirty of 261 patients (12%) with SLE seen in this hospital were men. Arthritis was less common as a first symptom in the men, although this group of patients had discoid lesions and serositis more often than the women. During the follow up a lower incidence of arthritis and malar rash and a higher incidence of other skin complications including discoid lesions and subcutaneous lupus erythematosus was found in the men. The incidence of nephropathy, neurological disease, thrombocytopenia, vasculitis, and serositis, was similar in the two groups. No significant immunological differences were found between men and women. These features indicate that several gender associated clinical differences may be present in patients with SLE.
Resumo:
Aeromonas hydrophila és un bacil gram-negatiu, patogen oportunista d’animal i humans. La patogènesi d’A. Hydrophila és multifactorial. A fi d'identificar gens implicats en la virulència de la soca PPD134/91 d’A. hydrophila, vam realitzar experiments de substracció gènica, que van dur a la detecció de 22 fragments d’ADN que codificaven 19 potencials factors de virulencia, incloent un gen que codificava una proteïna de sistema de secreció de tipus III (T3SS). La importància creixent del T3SS en la patogènesi de diversos bacteris, ens va dur a identificar i analitzar l'agrupació gènica del T3SS de les soques AH-1 i AH-3 d’A. hydrophila. La inactivació dels gens de T3SS aopB i aopD d’A. hydrophila AH-1, i ascV d’A. hydrophila AH-3, comporta una disminució de la citotoxicitat, un increment de la fagocitosi, i una reducció de la virulència en diferents models animals. Aquests resultats demostren que el T3SS és necessari per a la patogenicitat. També vam clonar i seqüenciar una ADP-ribosiltransferasa (AexT) a la soca AH-3 d’A. hydrophila, i vam demostrar que aquesta toxina és translocada via el T3SS, sistema que al seu torn sembla ser induïble in vitro en condicions de depleció de calci. El mutant en el gen aexT de la soca AH-3 d’A. hydrophila va mostrar una lleugera reducció de la virulència, assajada amb diferents mètodes. Mitjançant l'ús de diferents sondes d’ADN, vam determinar la presència del T3SS en soques tant clíniques com ambientals de diferents espècies del gènere Aeromonas: A. hydrophila, A. veronii, i A. caviae, i la codistribució d'aquesta agrupació gènica i el gen aexT. Finalment, amb la finalitat d'estudiar la regulació transcripcional de l'agrupació gènica de T3SS i de l’efector AexT A. hydrophila AH-3, vam aïllar els promotors predits per l’operó aopN-aopD i el gen aexT, i els vam fusionar amb el gen reporter gfp (Green Fluorescence Protein). A més, vam demostrar que l'expressió d'ambdós promotors depèn de diferents components bacterians, com per exemple el sistema de dos components PhoP/PhoQ, el sistema de quorum sensing AhyI/AhyR, o el complex piruvat deshidrogenasa.
Resumo:
The effects of exposure to the type species for Karlodinium veneficum (PLY # 103) on immune function and histopathology in the blue mussel Mytilus edulis were investigated. Mussels from Whitsand Bay, Cornwall (UK) were exposed to K. veneficum (PLY # 103) for 3 and 6 days. Assays for immune function included total and differential cells counts, phagocytosis and release of extra cellular reactive oxygen species. Histology was carried out on digestive gland and mantle tissues. The toxin cell quota for K. veneficum (PLY #103) was measured by liquid chromatography-mass spectrometry detecting two separable toxins KvTx1 (11.6 ± 5.4 ng/ml) and KvTx2 (47.7 ± 4.2 ng/ml). There were significant effects of K. veneficum exposure with increasing phagocytosis and release of reactive oxygen species following 6 days exposure. There were no significant effects on total cell counts. However, differential cell counts did show significant effects after 3 days exposure to the toxic alga. All mussels produced faeces but not pseudofaeces indicating that algae were not rejected prior to ingestion. Digestive glands showed ingestion of the algae and hemocyte infiltration after 3 days of exposure, whereas mantle tissue did not show differences between treatments. As the effects of K. veneficum were not observed in the mantle tissue it can be hypothesized that the algal concentration was not high enough, or exposure long enough, to affect all the tissues. Despite being in culture for more than 50 years the original K. veneficum isolate obtained by Mary Parke still showed toxic effects on mussels.
Resumo:
El principal problema de les teràpies actuals contra el càncer es la baixa especificitat envers les cèl•lules tumorals, cosa que comporta gran quantitat d’efectes secundaris. Per això es important el desenvolupament de nous tipus de teràpies i sistemes d’alliberament efectius per als fàrmacs ja existents al mercat. En la immunoteràpia contra el càncer es pretén estimular el sistema immunològic per a eliminar les cèl•lules canceroses de manera selectiva. En aquest projecte s’han sintetitzat derivats de l’antigen peptídic de melanoma NY-ESO1 i s’ha estudiat la seva capacitat per a estimular el sistema immunològic com a vacunes contra el càncer. També s’han encapsulat el antígens peptídics en liposomes com a adjuvants i sistemes d’alliberament. De totes les variants peptídiques la que resultà més immunogènica fou la que contenia el grup palmitoil i el fragment toxoide tetànic en la seva estructura. La utilització de liposomes com a sistema adjuvant sembla una estratègia interessant per al disseny de vacunes contra el càncer donat que l’encapsulació del pèptid en liposomes va augmentar notablement la resposta immunològica de l’antigen. Per altra banda, s’han desenvolupat dendrímers basats en polietilenglicol com a sistemes alliberadors de fàrmacs per al tractament de tumors. El polietilenglicol és àmpliament utilitzat com a sistema d’alliberament de fàrmacs degut a les seves interessants propietats, augment de la solubilitat i dels temps de residència en plasma, entre d’altres. La metodologia química descrita permet la diferenciació controlada de varies posicions en la superfície del dendrímer a més del creixement del dendrímer fins a una segona generació. S’ha sintetitzat la primera generació del dendrímer contenint el fàrmac antitumoral 5-fluorouracil i s’han realitzat estudis de citotoxicitat comprovant que l’activitat del nanoconjugat és del mateix ordre de magnitud que el 5-fluorouracil sense conjugar.
Resumo:
La migrafia es una cefalea en cuya etiologia intervienen factores muy diversos. En este trabajo, se revisan 10s resultados de diferentes investigaciones y se proponen pautas para un modelo integrador en el que 10s factores precipitantes del ataque de migraña ('a sean nerviosos, endocrinos, metabólicos o inmunológicos) ven facilitado su poder como desencadenantes a causa de la existencia de un estado de estrés crónico en el paciente
Resumo:
Induced pluripotent stem cells (iPSC ) provide an invaluable resource for regenerative medicine as they allow the generationof patient-specific progenitors with potential value for cell therapy. However, in many instances, an off-the-shelf approach isdesirable, such as for cell therapy of acute conditions or when the patient’s somatic cells are altered as a consequence of a chronicdisease or aging. Cord blood (CB) stem cells appear ideally suited for this purpose as they are young cells expected to carryminimal somatic mutations and possess the immunological immaturity of newborn cells; additionally, several hundred thousandimmunotyped CB units are readily available through a worldwide network of CB banks. Here we present a detailed protocol for thederivation of CB stem cells and how they can be reprogrammed to pluripotency by retroviral transduction with only two factors(OCT 4 and SO X2) in 2 weeks and without the need for additional chemical compounds.
Resumo:
Background Multiple Sclerosis (MS) is an acquired inflammatory demyelinating disorder of the central nervous system (CNS) and is the leading cause of nontraumatic disability among young adults. Activated microglial cells are important effectors of demyelination and neurodegeneration, by secreting cytokines and others neurotoxic agents. Previous studies have demonstrated that microglia expresses ATP-sensitive potassium (KATP) channels and its pharmacological activation can provide neuroprotective and anti-inflammatory effects. In this study, we have examined the effect of oral administration of KATP channel opener diazoxide on induced experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. Methods Anti-inflammatory effects of diazoxide were studied on lipopolysaccharide (LPS) and interferon gamma (IFNy)-activated microglial cells. EAE was induced in C57BL/6J mice by immunization with myelin oligodendrocyte glycoprotein peptide (MOG35-55). Mice were orally treated daily with diazoxide or vehicle for 15 days from the day of EAE symptom onset. Treatment starting at the same time as immunization was also assayed. Clinical signs of EAE were monitored and histological studies were performed to analyze tissue damage, demyelination, glial reactivity, axonal loss, neuronal preservation and lymphocyte infiltration. Results Diazoxide inhibited in vitro nitric oxide (NO), tumor necrosis factor alpha (TNF-¿) and interleukin-6 (IL-6) production and inducible nitric oxide synthase (iNOS) expression by activated microglia without affecting cyclooxygenase-2 (COX-2) expression and phagocytosis. Oral treatment of mice with diazoxide ameliorated EAE clinical signs but did not prevent disease. Histological analysis demonstrated that diazoxide elicited a significant reduction in myelin and axonal loss accompanied by a decrease in glial activation and neuronal damage. Diazoxide did not affect the number of infiltrating lymphocytes positive for CD3 and CD20 in the spinal cord. Conclusion Taken together, these results demonstrate novel actions of diazoxide as an anti-inflammatory agent, which might contribute to its beneficial effects on EAE through neuroprotection. Treatment with this widely used and well-tolerated drug may be a useful therapeutic intervention in ameliorating MS disease.
Resumo:
OBJECTIVE To determine the prevalence and clinical significance of hepatitis G virus (HGV) infection in a large cohort of patients with primary Sjögren¿s syndrome (SS). PATIENTS AND METHODS The study included 100 consecutive patients (92 female and eight male), with a mean age of 62 years (range 31¿80) that were prospectively visited in our unit. All patients fulfilled the European Community criteria for SS and underwent a complete history, physical examination, as well as biochemical and immunological evaluation for liver disease. Two hundred volunteer blood donors were also studied. The presence of HGV-RNA was investigated in the serum of all patients and donors. Aditionally, HBsAg and antibodies to hepatitis C virus were determined. RESULTS Four patients (4%) and six volunteer blood donors (3%) presented HGV-RNA sequences in serum. HGV infection was associated with biochemical signs of liver involvement in two (50%) patients. When compared with primary SS patients without HGV infection, no significant differences were found in terms of clinical or immunological features. HCV coinfection occurs in one (25%) of the four patients with HGV infection. CONCLUSION The prevalence of HGV infection in patients with primary SS is low in the geographical area of the study and HCV coinfection is very uncommon. HGV infection alone does not seen to be an important cause of chronic liver injury in the patients with primary SS in this area.
Resumo:
Les anomenades malalties neurodegeneratives tenen una simptomatologia i unes manifestacions clíniques molt diferents entre elles. No obstant, totes elles convergeixen en el mateix procés final, la neurodegeneració, que es manifestarà en diferents localitzacions o tipus cel·lulars del sistema nerviós. Nosaltres, plantegem la hipòtesi de que els processos moleculars i cel·lulars subjacents a la neurodegeneració són comuns per totes elles. Després de dur a terme un procés de selecció, es decideix treballar amb la malaltia de Parkinson, la d’Alzheimer, l’Esclerosi lateral amiotròfica i l’esclerosi múltiple. Hem pogut determinar que hi ha set processos moleculars o cel·lulars que estan associats al procés de neurodegeneració i que són comuns a totes elles. Havent-les estudiat per separat s’observa que el procés de neurodegeneració consisteix en una fallada en cadena de diferents sistemes moleculars i cel·lulars que tenen com a punt d’origen l’estrès oxidatiu. A aquest estrès s’hi pot arribar de diferents maneres. Una d’elles és l’exposició excessiva a certs metalls, que provoca la pèrdua dels sistemes antioxidants cel·lulars. Degut a això, els mitocondris reben un impacte oxidatiu massa gran i comencen a fallar. El fet que aquest orgànul actuï com a tampó del calci intracel·lular en provoca la seva desregulació, alterant d’aquesta manera el senyal nerviós. En resposta a l’estrès oxidatiu i tèrmic que genera la disfunció mitocondrial, s’activen les Proteïnes de Xoc Tèrmic (HSP) que actuant de citocines i presentadores d’antígens, inicien la resposta immunològica contra les cèl·lules danyades. Paral·lelament, s’observa un increment de la permeabilitat de la barrera hematoencefàlica degut a la pèrdua de les adhesions cel·lulars estretes per l’alta presència d’espècies reactives. Com a conseqüència de l’afebliment o el trencament de la barrera hematoencefàlica, es pot produir una entrada al SNC de diferents substàncies neurotòxiques i de cèl·lules del sistema immunitàri que, en condicions normals tenen l’accés restringit. Juntament amb aquestes cèl·lules immunològiques, també s’activen les cèl·lules del sistema immunitari innat residents al cervell, la micròglia, i totes elles secreten citocines proinflamatòries que contribueixen al procés de neurodegeneració. Nosaltres presentem els mecanismes pels quals aquesta inflamació, lluny d’atenuar-se, es cronifica per l’acció de certs bucles de retroalimentació positiva. Les diferents peculiaritats de cada malaltia contribueixen en aquest procés de diferents maneres, com és el cas dels pèptids β-amilides en la malaltia d’Alzheimer, l’α-sinucleina en el Parkinson, la superòxid dismutasa (SOD) en l’esclerosi lateral amiotròfica, o l’infiltració de leucòcits al cervell degut a la resposta autoimmune de l’esclerosi múltiple.Deixant de banda aquestes diferències, si el procés és comú entre totes elles, l’estudi a fons d’aquest procés hauria de poder permetre identificar dianes tarapèutiques que siguin comunes per les quatre malalties.
Resumo:
Immunological pressure encountered by protozoan parasites drives the selection of strategies to modulate or avoid the immune responses of their hosts. Here we show that the parasite Entamoeba histolytica has evolved a chemokine that mimics the sequence, structure, and function of the human cytokine HsEMAPII (Homo sapiens endothelial monocyte activating polypeptide II). This Entamoeba EMAPII-like polypeptide (EELP) is translated as a domain attached to two different aminoacyl-tRNA synthetases (aaRS) that are overexpressed when parasites are exposed to inflammatory signals. EELP is dispensable for the tRNA aminoacylation activity of the enzymes that harbor it, and it is cleaved from them by Entamoeba proteases to generate a standalone cytokine. Isolated EELP acts as a chemoattractant for human cells, but its cell specificity is different from that of HsEMAPII. We show that cell specificity differences between HsEMAPII and EELP can be swapped by site directed mutagenesis of only two residues in the cytokines' signal sequence. Thus, Entamoeba has evolved a functional mimic of an aaRS-associated human cytokine with modified cell specificity.
Resumo:
OBJECTIVE To determine the prevalence and clinical significance of hepatitis G virus (HGV) infection in a large cohort of patients with primary Sjögren¿s syndrome (SS). PATIENTS AND METHODS The study included 100 consecutive patients (92 female and eight male), with a mean age of 62 years (range 31¿80) that were prospectively visited in our unit. All patients fulfilled the European Community criteria for SS and underwent a complete history, physical examination, as well as biochemical and immunological evaluation for liver disease. Two hundred volunteer blood donors were also studied. The presence of HGV-RNA was investigated in the serum of all patients and donors. Aditionally, HBsAg and antibodies to hepatitis C virus were determined. RESULTS Four patients (4%) and six volunteer blood donors (3%) presented HGV-RNA sequences in serum. HGV infection was associated with biochemical signs of liver involvement in two (50%) patients. When compared with primary SS patients without HGV infection, no significant differences were found in terms of clinical or immunological features. HCV coinfection occurs in one (25%) of the four patients with HGV infection. CONCLUSION The prevalence of HGV infection in patients with primary SS is low in the geographical area of the study and HCV coinfection is very uncommon. HGV infection alone does not seen to be an important cause of chronic liver injury in the patients with primary SS in this area.